[Plate XVI]., Fig. 2.
- 1873. Craterium minimum Berk. & C., Grev., II., p. 67.
- 1892. Craterium cylindricum Massee, Mon., p. 268.
- 1894. Craterium leucocephalum Ditm., List., Myc., p. 72, in part.
- 1899. Craterium minimum Berk. & C., Macbr., N. A. S., p. 77.
- 1911. Craterium leucocephalum var. cylindricum List., Mycetozoa, 2nd ed., p. 97.
Sporangia closely gregarious, very small, .5 µ or less, slender, cylindric, almost entirely white, stipitate, the peridium delicate, transparent although calcareous nearly to the base, opening by a dehiscence regularly circumscissile; stipe short, about one-third the total height, clear orange-brown, somewhat furrowed, rising from an indistinct hypothallus; capillitium very lax, physaroid, the calcareous nodules large, rounded, pure white, aggregated at the centre of the cup; spore-mass black, spores minutely roughened, violaceous-brown, 8–9 µ.
This is the common form in the United States. Massee describes it as C. cylindricum Mass., and it seems not to occur in Europe. Lister has put it in with C. leucocephalum, from which its more delicate structure and elegant cylindrical shape certainly distinguish it. The dehiscence is even more regular than in the preceding species and approaches that of C. minutum Leers., with bleached forms of which it must not be confused. N. A. F., 1400.
C. minimum Berk. & C. has here priority. Massee regards this name as indicating a distinct species. We have been unable to determine what the authors really had before them, and adopt accordingly the first available combination.
New England to Iowa and south; reported also from the orient.
5. Craterium concinnum Rex.
- 1893. Craterium concinnum Rex, Proc. Phila. Acad., p. 370.
Sporangia scattered, usually minute, broadly funnel-shaped, stipitate. The peridium simple, variously colored by innate lime granules, opening by a regular cap or operculum, brownish white, darkest in the centre, always more or less convex; stipe equalling the cup in height, dark brown, longitudinally ridged; the capillitium a close-meshed network, with small rounded or slightly angular masses of ochre-brown lime-granules, larger toward the centre; spores pale brown, minutely warted, 9–10 µ.
This species differs from the following, to which it seems most nearly allied, in form, color, as in the capillitium, and color of the spores. In habitat, however, it seems no less distinct, being found always (?) on the spines of decaying chestnut-burs lying on the ground, and in company with that other peculiar species Lachnobolus globosus.